From: "DJ" Subject: '97 Dodge Dakota Oil Pressure Drop when Warm Date: Wednesday, December 06, 2006 12:30 PM
'97 Dodge Dakota 4x4 5.2L
I have been chasing this oil pressure problem around and decided to see what this group thinks. The OP is 40+ when started and remains until normal operating temperature is achieved. It then drops down to ~20psi or the low range on the gauge, but not below the lower limit indicator. When under acceleration or load it sounds like lifter rattle. I replaced the sending unit because the old one wouldn't read the low signal and dropped the gauge to 0psi. New filter and oil (20W-50 Florida) and still not maintaining the pressure when normal operating temp. I read a post on a web site that explained the 'Thrust Bearing' was bad which allowed a 1/8" shift in the crank position and after replacing the thrust bearing (and I would expect the rest of the mains) the oil pressure drop when warm disappeared. I would think that if the thrust bearing was bad that it would have the pressure problem even when the engine was cold or just warming up. I can drive it 45,
55, and the pressure still remains at 40+ until it reaches N.O.T. and then drops to the lower range of the gauge (~20psi?). That makes me think along the lines of a viscosity problem or a pump that has worn impellers. IE. the oil remains thick enough for the pump to work at lower temperatures but as soon as the oil is hot and the viscosity drops the problem surfaces. Any comments on your experiences with fixing this problem would be appreciated. remove no spam to emailDJ